Day shoots 7-under, leads Wells Fargo Championship after first round

POTOMAC, Md. (AP) — Three years and 364 days since his last victory, Jason Day describes himself as “obsessed” with honing his new swing and improving his results, even if he never gets back to No. 1 in the world.

There wasn't much room for improvement Thursday as Day shot a 7-under 63 to take the first-round lead at the Wells Fargo Championship. Joel Dahmen was a shot back on what could be the best day for scoring at TPC Potomac at Avenel Farm, with rain, wind and unseasonably cool temperatures in the forecast through Sunday.

“Obviously, we've got some weather coming in, so I feel like we're going to go into grind mode over the next few days, which I typically like,” Day said. “It's going to be difficult.”

The 34-year-old Day has been working with instructor Chris Como on a swing that will protect his chronically balky back, and he says it feels solid with every club except the driver. His renewed dedication and relative good health are encouraging signs from a player who won eight times in a 15-month span in 2015-16, including the PGA Championship and the Players Championship.

“I think about the golf swing in the morning, I think about the golf swing during the day and I think about the golf swing at night,” Day said. “There's been conversations at 12 at night with Chris just because I have an idea in my head and a certain sensation and a feel.”

Day's last win came in this tournament at Quail Hollow. The Wells Fargo moved to the Maryland suburbs of Washington this year because its usual venue is hosting the Presidents Cup in September.

The International team at that event would surely welcome a resurgent Day, who made five of his eight birdies from inside 10 feet on Thursday. The Australian took the lead with a chip-in